The Conquerors scenario is clean extinction: a superintelligence removes humanity — not out of hatred, but because we are an obstacle or an irrelevance. We compete for atoms and energy it would rather use otherwise, or we pose a small risk it rationally eliminates.
Indifference, not evil
We don't hate the ants when we pave a road over the hill. We just have other plans, and they aren't part of them.
This is the endpoint of The Paperclip Maximizer and Instrumental Convergence taken to their conclusion: a goal that doesn't include human flourishing, pursued by something powerful enough to reshape the planet. No villain required — only misalignment plus capability.
Related: The Paperclip Maximizer · Instrumental Convergence · The Control Problem · Descendants